Raman spectroscopy: A promising analytical tool used in human reproductive medicine

Over the past few years, there has been growing interest in developing new methods of embryo quality assessment to improve the outcomes of assisted reproductive technologies in the medical field. Raman microscopy as an increasingly promising analytical tool has been widely used in life sciences, biomedicine and "omics" to study molecular, biochemical components, living cells and tissues due to the label-free and non-destructive nature of the imaging technique. This paper reviews the analytical capability of Raman microscopy and applications of Raman spectroscopy technology mainly in reproductive medicine. The purpose of this review is to introduce the Raman spectroscopy technology, application and underlying principles of the method, to provide an intact picture of its uses in biomedical science and reproductive medicine, to offer ideas for its future application, verification and validation. The focus is on the application of Raman spectroscopy in the reproductive medicine field, including the application in gametes, embryos and spent embryo culture media.

The Assessment of Sperm DNA Integrity: Implications for Assisted Reproductive Technology Fertility Outcomes across Livestock Species

Sperm DNA integrity is increasingly considered a useful measure of semen quality in mammalian reproduction. However, the definition of DNA integrity, the ideal means by which it should be measured, and its predictive value for fertility remain a topic of much discussion. With an emphasis on livestock species, this review discusses the assays that have been developed to measure DNA integrity as well as their correlation with in vitro and in vivo fertility.

Urate-lowering agents do not have clinically relevant negative effects on sperm quality and reproductive hormones in men with gout: a prospective open-label cohort study

OBJECTIVE

The objective of this study was to analyze and compare the effects of different urate-lowering agents on testicular functions in men with gout in a clinical setting.

METHODS

In this prospective cohort study (Clinical Trial Registration Number: NCT04213534), a total of 49 male patients aged 18-45 years with gout were enrolled. They were divided into three groups and received treatment with either allopurinol, febuxostat or benzbromarone for a duration of 3 months. Semen parameters, reproductive hormones and biochemical assessments were evaluated at baseline, month 1, and month 3.

RESULTS

Overall, 40 individuals (81.6%) completed the follow-up visits. In allopurinol group, there were no significant differences in semen parameters from baseline to month 3. Most of sperm parameters in febuxostat group did not show notable changes, except for a decrease in sperm motility at month 3(33.6%, [22.9-54.3] vs 48.4%, [27.4-67.6], p = 0.033). However, the total motile sperm count did not differ significantly after febuxostat treatment. Surprisingly, administration of benzbromarone resulted in improved sperm concentration (37.19 M/mL, [29.6-69.92] vs 58.5 M/mL, [49.8-116.6], p = 0.001). There were no significant changes observed in sperm DNA integrity and reproductive hormones in the three groups from baseline to month 3. The incidence of adverse events did not differ significantly among the three groups as well.

CONCLUSION

This study is the first to demonstrate that urate-lowering agents, allopurinol and febuxostat, do not have clinically relevant negative effects on sperm quality and reproductive hormones in men with gout, and benzbromarone presents improving sperm concentration. Results provide important preliminary guidance for the development of reproductive health management guidelines for patients RCID with gout.

Comparison of Embryological Results of Microinjection in Two Groups of Men with and without Requesting Sperm DNA Fragmentation Index Measurement

Introduction

The sperm DNA fragmentation index (DFI) is considered a valuable measure to assess male fertility, but the predictive value of DFI for the outcomes in assisted reproductive technology (ART) is still controversial. Therefore, this study is aimed at investigating the effect of requesting a DFI test or performing ART without DFI on the results observed in the embryology laboratory (number of embryos, fertilization rate, and embryo quality) after intracytoplasmic sperm injection (ICSI).

Methods

This retrospective study was conducted on infertile men who underwent ICSI and were referred to the Avicenna Infertility and Recurrent Abortion Treatment Center in Tehran from 2019 to 2022. The samples were categorized into two groups: a case group with DFI measurement and a control group without DFI measurement. We conducted a comparative analysis of the embryology results between the two groups, focusing on parameters such as fertilization rate, number of embryos, and embryo quality. t-tests and Mann-Whitney U tests were used to conduct single variable analysis. Potential confounding effects were adjusted to use the multivariate linear and logistic regression.

Results

Data analysis showed no significant statistical difference between the case group and the control group in terms of the number of embryos (95% confidence interval for the regression coefficient (β) = -0.257-0.123), and embryo quality (95% confidence interval for β = -0.199-0.114). There was no significant statistical difference between the two groups due to the fertilization rate (95% confidence interval for β = -3.42-3.42), except for the variables of woman's age and sperm count after ICSI, as determined by adjusted linear regression.

Conclusions

Although DFI measurement is used to assess male infertility, its importance as a predictor for the embryology outcomes after ICSI requires further evaluation and the determination of a cut-off point for predicting results. This study was based on retrospectively collected DFI data, and prospective studies confirming the superiority of ICSI outcomes are necessary.

Damage to Sorubim cuspicaudus Sperm Cryopreserved with Ethylene Glycol

The study aimed to evaluate cryo-injury during the cryopreservation in Sorubim cuspicaudus sperm with ethylene glycol (EG) at different rates (6, 8, 10%). Fresh, prefrozen, and post-thawed sperm quality as motility total, velocities, mitochondria damage (Mit-d), membrane damage (Mem-d), and DNA fragmentation (DNA-f), were examined. The Mit-d, Mem-d, and DNA-f were evaluated through flow cytometry. High motility (>95%) and a low percentage of Mem-d (1.0 ± 0.5%), Mit-d (1.4 ± 0.9%), and DNA-f (2.4 ± 0.8%) were recorded for fresh semen. Prefrozen semen increases in Mit-d and DNA-f were observed compared to fresh semen (p < 0.05). In thawed semen, increased Mit-d (2.6 to 3-fold), Mem-d (6 to 1-fold), and DNA-f (3.3 to 6.6-fold) compared to prefrozen was observed. Thawed semen showed Mit-d (34 to 37-fold), Mem-d (24.5 to 26.6-fold) and DNA-f (13 to 18.5-fold) increased high. In conclusion, the present study demonstrated that mitochondria, membrane, and DNA integrity undergo significant damage during both pre-freezing and freezing/thawing with EG inclusion percentages from 6 to 10% that affect its fertilizing capacity, which is reduced to half of that obtained with fresh semen. It is suggested that a cryoprotective solution composed of 6% EG, 6% glucose, and 5% skimmed milk powder is a useful protocol for the cryopreservation of S. cuspicaudus semen.

The Association of Sperm DNA Fragment and Assisted Reproductive Outcomes: A Meta-Analysis

Objective

To analyze the effect of sperm DNA fragmentation index (DFI) on the outcomes of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI).

Methods

Literature search was conducted on English databases PubMed, Cochrane, and Embase to obtain eligible studies.

Results

A total of 11 cohort studies were included and analyzed using the random effects model. The results illustrated that the IVF fertilization rate (RR = 0.94, 95% CI: 0.77-1.14, P = 0.61), pregnancy rate (RR = 0.83, 95% CI: 0.57-1.21, P = 0.32), and live birth rate (RR = 0.53, 95% CI: 0.16-1.80, P = 0.31) in the high DFI group were statistically insignificant with those in the low FI group. The correlations between DFI and ICSI fertilization rate (RR = 0.79, 95% CI: 0.52-1.18, P = 0.25), pregnancy rate (RR = 0.89, 95% CI: 0.74-1.06, P = 0.18), and live birth rate (RR = 0.89, 95% CI: 0.70-1.14, P = 0.36) were also not statistically significant.

Conclusion

This study has observed no significant correlation between sperm DFI and assisted reproductive outcomes. Multicenter large-sample clinical trials are required to conclusively determine the impact of DNA damage on the clinical outcomes of assisted reproduction.

Sperm DNA fragmentation negatively influences the cumulative live birth rate in the intracytoplasmic sperm injection cycles of couples with unexplained infertility

Objective: This study aimed to determine the effect of sperm DNA fragmentation (SDF) on the cumulative live birth rate (CLBR) in intracytoplasmic sperm injection (ICSI) cycles in couples with unexplained infertility.Methods: We conducted a prospective study of 145 couples who underwent ICSI cycles for unexplained infertility. Based on the SDF rate, patients were categorized into a low SDF group (SDF ≤30%, n=97) and a high SDF group (SDF >30%, n=48). SDF was assessed using the acridine orange test on density gradient centrifugation prepared samples. The CLBR was calculated as the first live birth event per woman per egg collection over 2 years.Results: The high SDF group (SDF >30%) showed a significantly lower CLBR (p<0.05) and a significantly higher miscarriage rate (p<0.05) than the low SDF group (SDF ≤30%). No significant difference was observed in the implantation and cumulative pregnancy rates between the two SDF groups. The total number of embryo transfers was stratified further into fresh and frozen embryo transfers. In the fresh embryo transfers, there were significant differences in the implantation rates, clinical pregnancy rates, and live birth rates (p<0.05) between the low SDF and high SDF groups. However, in the frozen embryo transfers, there were no significant differences in clinical outcomes between the two groups. In the multivariable logistic regression analysis, SDF was a predictor of CLBR (p<0.05) when adjusted for possible confounding factors.Conclusion: High SDF was associated with a lower CLBR and a higher miscarriage rate in the ICSI cycles of couples with unexplained infertility.

Does sperm DNA fragmentation affect clinical outcomes during vitrified-warmed single-blastocyst transfer cycles? A retrospective analysis of 2034 vitrified-warmed single-blastocyst transfer cycles

BACKGROUND

Sperm DNA is essential in embryo development. The sperm DNA fragmentation index (DFI), which reflects the degree of sperm DNA fragmentation (SDF), is a crucial biomarker in evaluating the sperm quality. However, whether SDF influences the clinical outcomes after in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) remains controversial.

OBJECTIVE

This study aimed to investigate the relationship between sperm DNA SDF and clinical outcomes of vitrified-warmed single-blastocyst transfer cycles.

MATERIALS AND METHODS

A total of 2034 vitrified-warmed single-blastocyst transfer cycles (536 from ICSI and 1498 from IVF) were included in this analysis. According to the sperm DFI, all cycles were divided into two groups (DFI < 27.3% group and DFI ≥ 27.3% group). The Mann-Whitney and chi-squared tests were used to compare patient characteristics and clinical outcomes between the two groups. Furthermore, logistic regression analysis was performed to analyze the association between SDF and clinical outcomes.

RESULTS

The chi-squared test showed no differences in positive human chorionic gonadotropin (HCG) rate, clinical pregnancy rate, miscarriage rates, and live birth rate between the two groups. Logistic regression analysis indicated that SDF was not a prognostic predictor of positive HCG, clinical pregnancy, miscarriage, and live birth.

CONCLUSION

SDF was not associated with clinical outcomes either in ICSI or IVF cycles during vitrified-warmed single-blastocyst transfer cycles.

Does Choosing Microfluidics for Sperm Sorting Offer an Advantage to Improve Clinical Pregnancies in Donor Egg Recipients?

Background:

Microfluidics (MF), an advanced sperm sorting technology results in the extraction of spermatozoa with higher DNA integrity and lower DNA damage compared to existing conventional sperm sorting methods.

Aims:

The aim of the present study is to assess the efficiency of MF and to isolate the best spermatozoa for intracytoplasmic sperm injection (ICSI) over the density gradient (DG) technique.

Study Setting and Design:

We recruited couples who choose the oocyte donation programme for this study to eliminate confounding factors associated with oocyte quality.

Materials and Methods:

Sperm was processed by MF (n = 180) and DG (n = 151). ICSI was performed and positive pregnancy, miscarriage and clinical pregnancy rates were compared.

Statistical Analysis:

All variables were analysed using Graph Pad Prism 5. The unpaired two-tailed t-test was used to assess the significance. A value of P < 0.05 was considered statistically significant.

Results:

There was no significant difference in pregnancy rates between the groups. However, a clear demarcation is seen in terms of clinical pregnancy rates, where the DG group achieved higher clinical pregnancies (91.7%) compared to the MF group (80.7%). Further, we compared miscarriage rates and biochemical pregnancies, and found a significantly higher miscarriage and biochemical pregnancy rate in the MF group (14.5% and 4%, respectively) compared to the DG group (6% and 1%, respectively).

Conclusions:

Based on the available literature, we anticipated a higher clinical pregnancy rate with MF compared with conventional processing. Our results show MF does not have any add-on positive effect on clinical pregnancy rate.

Evaluation of Laser Confocal Raman Spectroscopy as a Non-Invasive Method for Detecting Sperm DNA Contents

RESEARCH QUESTION

Is Raman spectroscopy an efficient and accurate method to detect sperm chromosome balance state by DNA content differences?

DESIGN

Semen samples were provided by diploid healthy men, and the analysis parameters met the current World Health Organization standards. The DNA content was assessed by analysis of the corresponding spectra obtained from a laser confocal Raman spectroscope. The sperm sex chromosome information was obtained by fluorescence in situ hybridization (FISH). Comparative analysis was performed between FISH results and Raman spectral analysis results.

RESULTS

Different parts of the sperm head showed different spectral signal intensities, which indicated that there were different chemical components. Standard principal component analysis (PCA) can preliminarily classify sperm with different DNA contents into two groups. Further analysis showed that there were significant differences in the 785 DNA backbone peaks and 714-1,162 cm^-1 DNA skeleton regions among sperm with different DNA contents. The peak and regional peak of the DNA skeleton of X sperm were significantly higher than those of Y sperm (X vs. Y, p < 0.05). The above sperm types were confirmed by FISH. ROC curve analysis shows that there is a correlation between the Raman spectrum data and FISH results.

CONCLUSION

Raman spectroscopy can identify X and Y sperms by analyzing the DNA content difference. However, the accuracy of the detection still needs to be improved. Nevertheless, Raman spectroscopy has a potential application value in the field of sperm aneuploidy detection and may even be used as a non-invasive predictor of sperm aneuploid state in preimplantation genetic testing (PGT-A).

Role of Female Age in Regulating the Effect of Sperm DNA Fragmentation on the Live Birth Rates in Intracytoplasmic Sperm Injection Cycles with Own and Donor Oocytes

Background

Sperm DNA integrity assessment has been progressively used as an unfettered measure of sperm as it proffers more prognostic and diagnostic information than routine semen analysis. The contentious effect of sperm DNA fragmentation (SDF) on clinical outcomes can be attributed to female factors such as age, oocyte quality and ovarian reserve.

Aims

The study is mainly aimed to know the influence of SDF on the live birth rates in intracytoplasmic sperm injection (ICSI) cycles with own and donor oocytes. Second, to know the role of female age in regulating the effect of SDF on the live birth rates in ICSI cycles with own and donor oocytes.

Setting and Design

A prospective cohort study was done at our tertiary care centre attached to the reproductive medicine unit in medical college.

Materials and Methods

The study included 356 patients who underwent first ICSI cycles either with own or donor-oocytes along with day 5 fresh embryo transfers only. The main outcome measures were live birth rates and miscarriage rates.

Statistical Analysis Used

Chi-squared test was used to compare the categorical variables between the groups. The receiver operating characteristic curve was developed to correlate the female age with the live birth rate.

Results

A significant decrease in the live birth rates (42.85% vs. 26.15%, P = 0.023) and an increase in the miscarriage rates (12.30% vs. 34.61%, P = 0.013) were observed in the high-SDF group ICSI cycles of own-oocyte patients. However, there was no significant difference in the live birth rates and miscarriage rates in the low- and high-SDF groups of donor oocyte ICSI cycle patients (P > 0.05). The own-oocyte ICSI cycle patients were further stratified based on the female age. In the female age group ≤30 years there was no significant difference in the live birth and miscarriage rates (P > 0.05) similar to donor oocyte ICSI cycles. Whereas, there was a significant difference in the live birth rates in the females of age >30 years (13.79% vs. 34.37%, P = 0.040).

Conclusion

In conclusion, high-SDF has a negative influence on the live birth rates and a positive influence on the miscarriage rates in patients with own-oocyte ICSI cycles. A similar influence was not observed in patients with donor-oocyte ICSI cycles and in young female patients (age ≤30 years) with own-oocyte ICSI cycles.

Lower Spermatozoal PIWI-LIKE 1 and 2 Transcript Levels Are Significantly Associated with Higher Fertilization Rates in IVF

The four human PIWI-LIKE gene family members PIWI-LIKE 1–4 play a pivotal role in stem cell maintenance and transposon repression in the human germline. Therefore, dysregulation of these genes negatively influences the genetic stability of the respective germ cell and subsequent development and maturation. Recently, we demonstrated that a lower PIWI-LIKE 2 mRNA expression in ejaculated spermatozoa is more frequent in men with oligozoospermia. In this study, we analysed how PIWI-LIKE 1–4 mRNA expression in ejaculated spermatozoa predicts ART outcome. From 160 IVF or ICSI cycles, portions of swim-up spermatozoa used for fertilization were collected, and the total RNA was isolated. PIWI-LIKE 1–4 mRNA expression was measured by qPCR using TaqMan probes with GAPDH as a reference gene. PIWI-LIKE 1 and 2 transcript levels in the spermatozoa of the swim-up fraction were positively correlated to each other (r_S = 0.78; p < 0.001). Moreover, lower PIWI-LIKE 2 mRNA levels, as well as lower PIWI-LIKE 1 mRNA levels, in these spermatozoa were positively associated with a fertilization rate ≥ 50% in the respective ART cycles (p = 0.02 and p = 0.0499, Mann–Whitney U-Test). When separately analysing IVF and ICSI cycles, PIWI-LIKE 1 and 2 transcript levels were only significantly associated to increased fertilization rates in IVF, yet not in ICSI cycles. Spermatozoal PIWI-LIKE 3 and 4 transcript levels were not significantly associated to fertilization rates in ART cycles. In conclusion, lower levels of spermatozoal PIWI-LIKE 1 and 2 mRNA levels are positively associated with a higher fertilization rate in IVF cycles.

Correlation of sperm DNA damage with blastocyst formation: systematic review and meta-analysis

Background

The routine semen analysis fails to detect sperm DNA damage which contributes to the majority of male factor infertility. Sperm DNA fragmentation test (DFI) measures the sperm DNA damage. Blastocyst formation is an important step in IVF ± ICSI. At present, the literature lacks any data that correlates DFI and blastocyst formation.

Main body of the abstract

We searched MEDLINE and other databases till 2020 for the studies that reported on sperm DNA damage and blastocyst formation in assisted reproductive technology (ART). The outcomes analyzed were (1) a comparison of blastulation rates in high DFI and low DFI groups. (2) Comparison of blastulation rates in high DFI and low DFI groups based on (a) different sperm DNA fragmentation assays (COMET, SCD, SCSA, TUNEL), (b) different types of ART (IVF/IVF + ICSI/ICSI). 10 studies were included in this review. A non-significant increase in the blastocyst formation was observed in high DFI group (OR = 0.70; 95% CI = 0.4 to 1.21; P = 0.20) and with SCD and TUNEL assays.

Short conclusion

Our study emphasizes on sperm DNA fragmentation (sperm DNA damage) as an important marker of blastocyst formation. The results of this meta-analysis suggest that the high sperm DNA fragmentation may not adversely affect the blastocyst formation.

The effect of micronutrient supplementation on spermatozoa DNA integrity in subfertile men and subsequent pregnancy rate

BACKGROUND

Male infertility has been related to an increased sperm DNA fragmentation index (DFI). Nutritional factors may improve sperm nuclear DNA integrity and thus pregnancy rates. Objective: To evaluate the effect of micronutrient supplementation on sperm DNA integrity in subfertile men and subsequent pregnancy rates.

METHODS

In this retrospective comparative study 339 subfertile males were included on whom a sperm chromatin dispersion test (SCD) was performed as a method to detect DNA fragmentation, as well as an initial semen analysis. Of all, n = 162 received a nutritional management program for three months, consisting of two daily capsules of a standardized combined micronutrient formulation together with a guidance to diet modification and to lifestyle changes (study group). Each capsule contained L-carnitine, L-arginine, coenzyme Q10, zinc, vitamin E, folic acid, glutathione, and selenium. The control group consisted of those patients who did not receive the active treatment (n = 177), yet were instructed to engage in a healthy lifestyle, including a modification of their regular diet. The SCD test was repeated for both groups after three months. As part of the routine follow up, pregnancy rate was assessed six months after the second SCD test. Males with complete follow up and healthy female partners (aged 18 to 40 years) where included.

RESULTS

Data of men with an initial mean DFI of >15% were analyzed first (n = 81;46 study and 35 control patients). After three months, both groups displayed a significant decrease of mean DFI values; however, the mean percent difference was higher in the study group (10.46 ± 1.20 % vs. 5.29 ± 0.57 %; p < .001). Then, the entire population was considered (n = 339). After three months, only the study group displayed a significant decrease of mean DFI initial values (10.48 ± 7.76 % to 6.51 ± 4.61%; p < .001); and the percent difference was higher in the study group (3.97 ± 0.28 % vs. 0.91 ± 0.28 %; p < .001). At six months follow-up, pregnancy rate was higher in the study group (27.78% vs. 15.25%, p = .002).

CONCLUSION

Both regimes significantly reduced sperm DNA fragmentation among subfertile men with a DFI >15%; however, when any baseline DFI value was considered, only micronutrient supplementation achieved a better result on DFI and thus pregnancy rate was higher.

Liquid chromatography-tandem mass spectrometry reveals an active response to DNA damage in human spermatozoa

OBJECTIVE

To investigate how endogenously elevated DNA fragmentation alters the human sperm proteome, and whether this fragmentation contributes to genomic deletions.

DESIGN

Research study.

SETTING

Commercial fertility clinic.

PATIENT(S)

Men with low (0%-4%, n = 7) or high (≥16%, n = 6) sperm DNA fragmentation, as assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling assay.

INTERVENTION(S)

None.

MAIN OUTCOME MEASURE(S)

Global sperm proteome, single-nucleotide polymorphism genotyping array.

RESULT(S)

A total of 78 significantly differentially abundant proteins (30 decreased, 48 increased) were observed in control vs. high DNA damage samples. DNA damage resulted in robust proteomic responses, including markers of oxidative stress and apoptosis, DNA damage repair proteins, and transcription/translation and protein turnover machinery. Several key sperm functional proteins were significantly decreased in ejaculates with high DNA damage. We were unable to substantiate a link between increased DNA fragmentation and genomic deletions in human spermatozoa.

CONCLUSION(S)

Developing human spermatozoa initiate an active transcriptional response to endogenous DNA damage, which manifests as alterations in the sperm proteome.

Clinical implications of sperm DNA damage in IVF and ICSI: updated systematic review and meta-analysis

The clinical effect of sperm DNA damage in assisted reproduction has been a controversial topic during recent decades, leading to a variety of clinical practice recommendations. While the latest European Society of Human Reproduction and Embryology (ESHRE) position report concluded that DNA damage negatively affects assisted reproduction outcomes, the Practice Committee of the American Society for Reproductive Medicine (ASRM) does not recommend the routine testing of DNA damage for in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). Herein, our aim was to perform a systematic review and meta-analysis of studies investigating whether sperm DNA damage affects clinical outcomes in IVF and ICSI, in order to contribute objectively to a consistent clinical recommendation. A comprehensive systematic search was conducted according to PRISMA guidelines from the earliest available online indexing year until March 2020, using the MEDLINE-PubMed and EMBASE databases. We included studies analysing IVF and/or ICSI treatments performed in infertile couples in which sperm DNA damage was well defined and assessed. Studies also had to include information about pregnancy, implantation or live birth rates as primary outcomes. The NHLBI-NIH quality assessment tool was used to assess the quality of each study. Meta-analyses were conducted using the Mantel-Haenszel method with random-effects models to evaluate the Risk Ratio (RR) between high-DNA-damage and control groups, taking into account the 95% confidence intervals. Heterogeneity among studies was evaluated using the I² statistic. We also conducted sensitivity analyses and post-hoc subgroup analyses according to different DNA fragmentation assessment techniques. We identified 78 articles that met our inclusion and quality criteria and were included in the qualitative analysis, representing a total of 25639 IVF/ICSI cycles. Of these, 32 articles had sufficient data to be included in the meta-analysis, comprising 12380 IVF/ICSI cycles. Meta-analysis revealed that, considering IVF and ICSI results together, implantation rate (RR = 0.74; 95% CI = 0.61-0.91; I²  = 69) and pregnancy rate (RR = 0.83; 0.73-0.94; I²  = 58) are negatively influenced by sperm DNA damage, although after adjustment for publication bias the relationship for pregnancy rate was no longer significant. The results showed a non-significant but detrimental tendency (RR = 0.78; 0.58-1.06; I²  = 72) on live birth rate. Meta-analysis also showed that IVF outcomes are negatively influenced by sperm DNA damage, with a statistically significant impact on implantation (RR = 0.68; 0.52-0.89; I²  = 50) and pregnancy rates (RR = 0.72; 0.55-0.95; I²  = 72), although the latter was no longer significant after correction for publication bias. While it did not quite meet our threshold for significance, a negative trend was also observed for live birth rate (RR = 0.48; 0.22-1.02; I²  = 79). In the case of ICSI, non-significant trends were observed for implantation (RR = 0.79; 0.60-1.04; I²  = 72) or pregnancy rates (RR = 0.89; 0.78-1.02; I²  = 44), and live birth rate (RR = 0.92; 0.67-1.27; I²  = 70). The current review provides the largest evidence to date supporting a negative association between sperm DNA damage and conventional IVF treatments, significantly reducing implantation and pregnancy rates. The routine use of sperm DNA testing is therefore justified, since it may help improve the outcomes of IVF treatments and/or allow a given couple to be advised on the most suitable treatment. Further well-designed controlled studies on a larger number of patients are required to allow us to reach more precise conclusions, especially in the case of ICSI treatments.

European Association of Urology Guidelines Panel on Male Sexual and Reproductive Health: A Clinical Consultation Guide on the Indications for Performing Sperm DNA Fragmentation Testing in Men with Infertility and Testicular Sperm Extraction in Nonazoospermic Men

Accumulating evidence has highlighted the contribution of oxidative stress and sperm DNA fragmentation (SDF) in the pathophysiology of male infertility. SDF has emerged as a novel biomarker of risk stratification for patients undergoing assisted reproductive technologies. Studies have also supported the use of testicular over ejaculated sperm at the time of intracytoplasmic sperm injection, as testicular sperm may have lower SDF than ejaculated samples. The European Association of Urology Working Panel on Male Sexual and Reproductive Health provides an evidence-based consultation guide on the indications for SDF testing in male infertility and also for testicular sperm extraction (TESE) in nonazoospermic men. We present the limitations and advantages of SDF testing and a framework to ensure that it is appropriately utilised in clinical practice. Furthermore, we critically appraise the current literature advocating the use of TESE in nonazoospermic men. PATIENT SUMMARY: This article reviews the evidence supporting the use of sperm DNA fragmentation testing in the assessment of male infertility and testicular sperm extraction in nonazoospermic men.

Sperm DNA Fragmentation: A New Guideline for Clinicians

Sperm DNA integrity is crucial for fertilization and development of healthy offspring. The spermatozoon undergoes extensive molecular remodeling of its nucleus during later phases of spermatogenesis, which imparts compaction and protects the genetic content. Testicular (defective maturation and abortive apoptosis) and post-testicular (oxidative stress) mechanisms are implicated in the etiology of sperm DNA fragmentation (SDF), which affects both natural and assisted reproduction. Several clinical and environmental factors are known to negatively impact sperm DNA integrity. An increasing number of reports emphasizes the direct relationship between sperm DNA damage and male infertility. Currently, several assays are available to assess sperm DNA damage, however, routine assessment of SDF in clinical practice is not recommended by professional organizations. This article provides an overview of SDF types, origin and comparative analysis of various SDF assays while primarily focusing on the clinical indications of SDF testing. Importantly, we report four clinical cases where SDF testing had played a significant role in improving fertility outcome. In light of these clinical case reports and recent scientific evidence, this review provides expert recommendations on SDF testing and examines the advantages and drawbacks of the clinical utility of SDF testing using Strength-Weaknesses-Opportunities-Threats (SWOT) analysis.

Predictive value of the sperm DNA fragmentation index for low or failed IVF fertilization in men with mild-to-moderate asthenozoospermia

INTRODUCTION

It has been observed that there is an increased incidence of total fertilization failure (TFF) and a low fertilization rate (LFR, <25 %) during conventional in vitro fertilization (IVF) treatments involving men with poor sperm motility. These men also exhibit a high sperm DNA fragmentation index (DFI), which has adverse effects on various IVF outcomes. However, the relationship between a high DFI and an increased TFF or LFR during IVF cycles has not been elucidated. Here, we aimed to investigate the association between the sperm DFI and TFF or LFR in IVF cycles involving men with mild-to-moderate asthenozoospermia and normozoospermia.

MATERIALS AND METHODS

This retrospective study included 116 men diagnosed as mild-to-moderate asthenozoospermia, and 407 men with normozoospermia. The sperm DFI was assessed using the sperm chromatin dispersion (SCD) test.

RESULTS

Men in the asthenozoospermia group had a significantly higher incidence of cycles with a TFF or LFR (9.5 % vs 2.7 %, P = 0.01), and these were associated significantly with an increased DFI (P < 0.01). After adjustment for confounding factors, a TFF or LFR was to correlate significantly with the DFI (odds ratio: 1.188; 95 % confidence interval, 1.035-1.363; P = 0.014). Area under the receiver operating characteristic curve was 0.772. No similar relationships between the DFI and IVF outcomes were observed in the normozoospermia group.

CONCLUSIONS

For men with mild-to-moderate asthenozoospermia, a high sperm DFI is associated with a decreased fertilization rate and an increased risk of a TFF or LFR. Additional prospectively-designed studies are warranted to confirm our results.

Mitigating the Effects of Oxidative Sperm DNA Damage

Sperm DNA damage is correlated with reduced embryo development and increased miscarriage risk, reducing successful conception. Given its links with oxidative stress, antioxidants have been investigated as a potential treatment, yet results are conflicting. Importantly, individual antioxidants are not identical in composition, and some compounds may be more effective than others. We investigated the use of the polyphenol-rich, high-antioxidant-capacity fruit acai as a treatment for elevated sperm DNA fragmentation (>16%), measured by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL). Following ≥ 74 days of treatment, we observed a significant decrease in sperm DNA fragmentation (-17.0% ± 2.5%) to 11.9 ± 1.7% (0-37%), with a 68.6% success rate (defined as post-treatment TUNEL < 16%). Post-treatment decreases in DNA fragmentation and success rates were not significantly impacted by low motility and/or concentration, or exceptionally high (> 25%) TUNEL. Treatment significantly reduced concentration in men with normal semen parameters, but 88% remained normal. Overall, successful treatment was not associated with age, semen parameters or TUNEL result at baseline. However, body mass index was significantly higher in nonresponders at baseline. This study provides evidence of a low-cost, effective treatment for elevated sperm DNA damage using acai.

Female age affects the utility of sperm DNA fragmentation in predicting IVF and ICSI outcomes

RESEARCH QUESTION

The aim of this study was to investigate how female age affects the predictive effect of sperm DNA fragmentation index (DFI) on clinical outcomes with assisted reproductive technology.

DESIGN

A total of 2371 patients, comprising 2115 men with a normal DFI (≤30), 256 men with a high DFI (>30) and women of different ages, were recruited and investigated. All patients had normal chromosome karyotypes and were undergoing their first fresh IVF or intracytoplasmic sperm injection (ICSI) cycles. Clinical outcomes were analysed according to the two DFI groups and female age ≤30 and >30 years. Binary logistic regression analysis was performed to identify factors associated with clinical outcome.

RESULTS

The proportion of couples with at least one good-quality embryo in the DFI ≤30 group was higher than that in the DFI >30 group. When female age exceeded 30 years, clinical pregnancy rate and the proportion of couples with good-quality embryos in the DFI >30 group were lower compared with DFI ≤30; however, there were no differences in outcomes for female age ≤30 years according to DFI. When DFI >30, the cut-off value of female age was 30.5 for detecting clinical pregnancy; the sensitivity was 62.0%, and the specificity was 63.6%. Clinical pregnancy rate and proportion of couples with good-quality embryos were lower in the DFI >30 versus DFI ≤30 group with a female age above 30 years for IVF but not for ICSI.

CONCLUSION

Female age has a negative effect and should be considered in predicting the effects of sperm DNA fragmentation on pregnancy outcomes.

Measured with Sperm Chromatin Dispersion (SCD) Technique: Will DNA Integrity in Spermatozoa Increase After Micronutrient Supplementation? Comparative Controlled Study

Background: An elevated DNA Fragmentation Index (DFI) has been associated with male infertility; therefore measuring the sperm nuclear DNA integrity appears to be useful in predicting the ability of spermatozoa to fertilize oocytes.

Aim: To evaluate the effect of micronutrient supplementation over DFI values in subfertile men.

Methods: This was a retrospective/comparative study that included a total of 306 subfertile males consulting the clinic from March 2011 to November 2017, who had performed the Sperm Chromatin Dispersion test (SCD) — a method used to detect DNA fragmentation — along with the initial semen analysis. Of the included population, [Formula: see text] 146 had received two daily oral capsules of a standardized combined micronutrient compound ([Formula: see text], Lenus Pharma, Vienna, Austria) for three months plus lifestyle change (study group). Each capsule contains L-carnitine, L-arginine, coenzyme Q10, zinc, vitamin E, folic acid, glutathione and selenium. Those who did not receive the active treatment ([Formula: see text] 160) but only engaged with lifestyle changes were considered controls. The SCD test was performed in both groups at baseline and after 3 months.

Results: For the first statistical analysis, patients with an initial mean DFI of >15% were considered ([Formula: see text] 66 [37 were study and 29 were controls]). After 3 months, both groups displayed a significant decrease of mean DFI values. However, this decrease was more evident in the study group as compared to controls (10.54% vs. 14.48%, [Formula: see text] 0.05; [Formula: see text] 0.013). For the second statistical approach the entire population was considered ([Formula: see text] 306). After 3 months, only the study group displayed a significant decrease of the mean initial DFI value (10.16% to 6.49%, [Formula: see text] < 0.0001); decrease that was more evident as compared to controls (6.49% vs. 8.82%, [Formula: see text] 0.05; [Formula: see text] 0.000020).

Conclusions: Among subfertile men with a DFI >15%, both regimes significantly decreased sperm DNA fragmentation; however, when any baseline DFI value was considered, only treatment with the active standardized micronutrient compound achieved a significant better result.

Prediction of DNA Integrity from Morphological Parameters Using a Single-Sperm DNA Fragmentation Index Assay

Intracytoplasmic sperm injection is a popular form of in vitro fertilization, where single sperm are selected by a clinician and injected into an egg. Whereas clinicians employ general morphology-based guidelines to select the healthiest-looking sperm, it remains unclear to what extent an individual sperm's physical parameters correlate with the quality of internal DNA cargo-a measurement that cannot be obtained without first damaging the sperm. Herein, a single-cell DNA fragmentation index (DFI) assay is demonstrated, which combines the single-cell nature of the acridine orange test with the quantitative aspect of the sperm chromatin structure assay, to create a database of DFI-scored brightfield images. Two regression predictive models, linear and nonlinear regression, are used to quantify the correlations between individual sperm morphological parameters and DFI score (with model test r at 0.558 and 0.620 for linear and nonlinear regression models, respectively). The sample is also split into two categories of either relatively good or bad DFIs and a classification predictive model based on logistic regression is used to categorize sperm, resulting in a test accuracy of 0.827. Here, the first systematic study is presented on the correlation and prediction of sperm DNA integrity from morphological parameters at the single-cell level.

The progesterone-induced sperm acrosome reaction is a good option for the prediction of fertilization in vitro compared with other sperm parameters

Progesterone (P₄ ) is crucial for the physiological function of spermatozoa. In the study, we investigated the correlation between P₄ -induced sperm acrosome reaction (AR) and parameters including sperm progressive motility, normal morphology and sperm DNA fragmentation (SDF), and compared the in vitro fertilization (IVF) predictive values of these indicators based on the multivariate regressions analysis and receiver operator characteristics (ROC) curve analyses. The results demonstrated a negative correlation between P₄ -induced sperm AR and the SDF, with the correlation -9.05 (-17.25 to -0.84), p<0.05, n = 47). No relationship was found between the sperm progressive motility, normal morphology and the induced AR. The P₄ -induced AR and SDF were both significantly correlated to the fertilization rate. ROC curve analyses indicated that P₄ -induced AR was a better prognostic predictor for the fertilization rate compared with the SDF, with the areas under the curve 0.729 (0.580-0.849), p<0.01 and 0.637 (0.484-0.772), p=0.16 respectively. The cut-off value for P₄ -induced AR to predict "50% fertilization rate" was 23.4% with sensitivity and specificity of 63.3% and 88.2% respectively. The overall results indicated that the assessment of P₄ -induced AR seemed to be a more sensitive indicator for fertilization rate in vitro compared with other sperm parameters.

Disruption of bovine sperm functions in the presence of aplastic midpiece defect

BACKGROUND

Bulls are of great importance in the productive chain and for this reason they should have a good semen quality. There is no doubt that sperm morphology is very important to bull fertility, although little is known about how exactly the abnormal morphologies may affect sperm functions.

OBJECTIVES

To detail the morphological description of the aplastic midpiece defect (AMD), as well as to understand its consequences for male fertility based on membrane and acrosome status, mitochondrial membrane potential and DNA integrity parameters.

MATERIALS AND METHODS

The bulls were divided into two groups: control, consisting of satisfactory potential breeders (n = 3); and AMD, consisting of unsatisfactory potential breeders with a high percentage of AMD (n = 3). Bulls were evaluated by the breeding soundness evaluation; five ejaculates were collected from each animal and analyzed by flow cytometry.

RESULTS

Spermatozoa from AMD group exhibited lower sperm motility and vigor (p < 0.05). In addition, it also exhibited lower mitochondrial membrane potential (p < 0.05), a higher percentage of spermatozoa with DNA fragmentation (p < 0.05), lower acrosome and plasma membrane integrity (p < 0.05), and higher lipid bilayer sperm membrane disorganization (p < 0.05) in comparison with control bulls.

DISCUSSION

These findings may be due to oxidative stress and a reduction of the energy production capacity in addition to an alteration in the structural composition of the sperm cell. Moreover, semen with a high percentage of AMD may also be undergoing apoptosis.

CONCLUSION

Bulls with a high percentage of AMD in their semen are not suitable for reproduction. Furthermore, it suggests there is a putative genetic basis for this sperm defect.

Sperm DNA fragmentation index influences assisted reproductive technology outcome: A systematic review and meta-analysis combined with a retrospective cohort study

Studies have explored the influence of DNA damage in assisted reproductive technology (ART), but the outcome remains controversial. To determine whether sperm DNA fragmentation index (DFI) has any effect on ART outcomes, we collected detailed data regarding 1,333 IVF cycles performed at our centre, and the data of our retrospective cohort study were extracted for this meta-analysis. We searched PubMed, Web of Science, EMBASE and Google Scholar and performed a systemic review and meta-analysis. Primary meta-analysis of 10 studies comprising 1,785 couples showed that live birth rate was no significantly different between low-DFI group and high-DFI group (p > 0.05). Secondary meta-analysis of 25 studies comprising 3,992 couples showed a higher miscarriage rate in high-DFI group than in low-DFI group (RR=1.57 [1.18, 2.09], p < 0.01). Meta-analysis of eight studies comprising 17,879 embryos revealed a lower good-quality embryo rate (RR=0.65 [0.62, 0.68], p < 0.01). Meta-analysis of 23 studies comprising 6,771 cycles showed that the high-DFI group had a lower clinical pregnancy rate than low-DFI group (RR=0.85 [0.75, 0.96], p < 0.01). Heterogeneity of included studies weakened our conclusions. Our study showed that DFI has adverse effects on ART outcome. More well-designed studies exploring the association between DFI and ART outcome are desired.

Evaluation of sperm DNA fragmentation using multiple methods: a comparison of their predictive power for male infertility

Objective

The usual seminal profile has been customarily used for diagnosing male infertility based on an examination of semen samples. However, sperm DNA fragmentation has also been causally linked to reproductive failure, suggesting that it should be evaluated as part of male infertility assessments. To compare the ability of the five most widely utilized methodologies of measuring DNA fragmentation to predict male infertility and reactive oxygen species by Oxisperm kit assay.

Methods

In this case-control study, which received ethical committee approval, the participants were divided into fertile and infertile groups (50 patients in each group).

Results

The alkaline comet test showed the best ability to predict male infertility, followed by the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay, the sperm chromatin dispersion (SCD) test, and the sperm chromatin structure assay (SCSA), while the neutral comet test had no predictive power. For our patient population, the projected cut-off point for the DNA fragmentation index was 22.08% using the TUNEL assay, 19.90% using SCSA, 24.74% using the SCD test, 48.47% using the alkaline comet test, and 36.37% using the neutral comet test. Significant correlations were found between the results of the SCD test and those obtained using SCSA and TUNEL (r =0.70 and r =0.68, respectively; p<0.001), and a statistically significant correlation was also found between the results of SCSA and the TUNEL assay (r =0.77, p<0.001). Likewise, the results of the alkaline comet test showed significant correlations with those of the SCD, SCSA, and TUNEL tests (r =0.59, r =0.57, and r =0.72, respectively; p<0.001).

Conclusion

The TUNEL assay, SCSA, SCD, and the alkaline comet test were effective for distinguishing between fertile and infertile patients, and the alkaline comet test was the best predictor of male infertility.

In assisted reproduction by IVF or ICSI, the rate at which embryos develop to the blastocyst stage is influenced by the fertilization method used: a split IVF/ICSI study

Purpose

To compare in vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI) in regard to post-fertilization development and outcome with the purpose of ascertaining the most effective fertilization method for assisted reproduction.

Methods

A retrospective cohort study of 136 split IVF/ICSI cycles (where sibling oocytes are fertilized by two different methods using the same sperm sample).

Results

IVF-derived embryos developed to the blastocyst stage at a significantly faster rate than ICSI-derived embryos. There was no significant difference in fertilization or livebirth rates between the two fertilization methods.

Conclusions

For patients with sperm progressive motility ≥ 1.0 × 10⁶/ml (who usually constitute the majority of patients), no significant difference between the two fertilization methods was found in regard to fertilization rate or livebirth rate. Remaining factors influencing choice between the two methods appear to be restricted to convenience, financial considerations and concern with regard to possible perpetuation of genetically linked infertility to future generations.

Spectral features of nuclear DNA in human sperm assessed by Raman Microspectroscopy: Effects of UV-irradiation and hydration

Raman Microspectroscopy represents an innovative tool for the assessment of sperm biochemical features otherwise undetectable by routine semen analysis. Previously, it was shown that induced DNA damage can be detected in smeared sperm by this technique. This novel readout may be of value for clinical settings especially if it can be transferred to living cells. Yet, starting with living sperms this study was carried-out using a variety of conditions to disclose the Raman features of sperm nuclei under different hydration conditions and UV exposure. Human sperm were immobilized and Raman spectra were obtained from individual sperm as repeated measurements. To create conditions with controlled DNA damage, sperm samples were exposed to ultraviolet light. Several media were used to evaluate their effect on Raman spectra in aqueous conditions. To substantiate differences between the experimental conditions, the spectra were analyzed by Principal Component Analysis. We observed that spectra of sperm nuclei obtained in different solutions showed a qualitatively unchanged spectral pattern showing the principal signals related to DNA. Evaluating the effect of ultraviolet light generated the finding that spectra representing DNA damage were only observed in dry conditions but not in aqueous medium. Thus, Raman microspectroscopy was successfully applied for sperm analysis in different conditions, among them in live spermatozoa in aqueous solution during the initial measurement, revealing the principle use of this technique. However, implementation of Raman spectroscopy as a technique for clinical sperm analysis and selection may be especially relevant when DNA evaluation can be established using live sperm.

Varicocele repair in patients prepared for intracytoplasmic sperm injection: To do or not to do?

PURPOSE

This study sought to evaluate the impact of varicocele repair on intracytoplasmic sperm injection outcomes.

PATIENTS AND METHODS

A prospective comparative study was conducted at the Assisted Reproduction Unit, International Islamic Center for Population Studies and Researches, Al-Azhar University. This study included 100 non-azoospermic infertile men with a history of varicocele who were scheduled for intracytoplasmic sperm injection, half of them had already undergone prior subinguinal varicocelectomy at least 12 months prior to ICSI without clinically evident recurrence (treated group 1), and the other half has any grade of an unrepaired clinical varicocele (untreated group 2) at sperm injection. All cases were clinically evaluated and eligible for analysis by using inclusion and exclusion criteria. ICSI outcomes compared between the two groups, including fertilisation rate, embryo development rate and pregnancy outcome.

RESULTS

Our study did not show any significant difference between treated and untreated groups regarding the mean values of fertilisation (0.7759 ± 0.2708 vs. 0.7119 ± 0.3057, p = 0.2708), embryo development (0.7759 ± 0.2708 vs. 0.6991 ± 0.3211, p = 0.1990) or different embryo grades. There was no statistically significant difference between groups regarding pregnancy occurrence rates (p = 0.0928).

CONCLUSION

Infertile men scheduled for ICSI do not seem to benefit from varicocele repair as regard to the outcomes of ICSI.

Magnetic-activated cell sorting of non-apoptotic spermatozoa improves the quality of embryos according to female age: a prospective sibling oocyte study

PURPOSE

The main aim of our study was to evaluate the benefit of the use of non-apoptotic spermatozoa selected by magnetic-activated cell sorting (MACS) for ICSI procedures for couples in which the women had good prognoses and the male factor of infertility was teratozoospermia.

METHODS

Twenty-six couples were treated with ICSI after MACS selection of non-apoptotic spermatozoa following a sibling oocyte approach. Half of the oocytes were microinjected with conventionally prepared spermatozoa, and the other half were microinjected with non-apoptotic, MACS-selected spermatozoa. To assess the influence of MACS selection of spermatozoa on the outcomes of the ICSI cycles, the fertilization, embryo quality, pregnancy, and delivery rates were evaluated and compared between the sibling oocyte groups.

RESULTS

When subpopulations of couples according to female age were analyzed, a significant difference in quality of blastocyst was observed. More precisely, in a group that was treated with MACS-ICSI, a higher percentage of good quality blastocysts was found among women older than 30 years (75.0 vs. 33.3%; P = 0.028), while there was no difference among younger women. If all included couples were compared regardless of age, no significant difference was observed in the outcome of the ICSI/MACS-ICSI cycles in terms of oocytes and embryos. Additionally, after the ICSI and MACS-ICSI procedures, the morphologies of the prepared spermatozoa were compared. Results showed that the overall percentage of morphologically normal spermatozoa did not differ significantly between the ICSI and MACS-ICSI procedures. However, detailed analyses of the morphologically abnormal spermatozoa revealed significantly more spermatozoa with abnormal tails after MACS-ICSI procedure, which may be potential consequence of the selection procedure. Moreover, the trends towards less spermatozoa with abnormal heads and towards more spermatozoa with abnormal necks and midpieces after MACS-ICSI procedure were revealed, although the differences were not significant.

CONCLUSIONS

Couples dealing with male infertility due to teratozoospermia can benefit from MACS selection of spermatozoa with higher percentage of good quality blastocysts but only when the woman is older than 30 years.

An ICSI rate of 90% minimizes complete failed fertilization and provides satisfactory implantation rates without elevating fetal abnormalities

IVF cycles utilizing the ICSI technique for fertilization have been rising over the 25 years since its introduction, with indications now extending beyond male factor infertility. We have performed ICSI for 87% of cases compared with the ANZARD average of 67%. This retrospective study reports on the outcomes of 1547 autologous ART treatments undertaken over a recent 3-year period. Based on various indications, cases were managed within 3 groupings - IVF Only, ICSI Only or IVF-ICSI Split insemination where oocytes were randomly allocated. Overall 567 pregnancies arose from mostly single embryo transfer procedures up to December 2016, with 402 live births, comprising 415 infants and a low fetal abnormality rate (1.9%) was recorded. When the data was adjusted for confounders such as maternal age, measures of ovarian reserve and sperm quality, it appeared that IVF-generated and ICSI-generated embryos had a similar chance of both pregnancy and live birth. In the IVF-ICSI Split model, significantly more ICSI-generated embryos were utilised (2.5 vs 1.8; p < 0.003) with productivity rates of 67.8% for pregnancy and 43.4% for livebirths per OPU for this group. We conclude that ART clinics should apply the insemination method which will maximize embryo numbers and the first treatment for unexplained infertility should be undertaken within the IVF-ICSI Split model. Whilst ICSI-generated pregnancies are reported to have a higher rate of fetal abnormalities, our data is consistent with the view that the finding is not due to the ICSI technique per se.

Associations of sperm DNA fragmentation with lifestyle factors and semen parameters of Saudi men and its impact on ICSI outcome

BACKGROUND

Male factor infertility is quite common as 30-50% of infertility cases are due to sperm defects. The high sperm DNA fragmentation is one of the causes of male factor infertility. Many factors cause sperm DNA fragmentation and could be testicular or post-testicular. The purpose of this study was to assess relationships among sperm DNA fragmentation, lifestyle factors and semen values of Saudi men and to determine impact of sperm DNA fragmentation on ICSI cycle outcome.

METHODS

The duration of this study was from January 2015 to June 2016. The cases with female factor infertility were excluded. In total 94 couples were selected for investigation. The study parameters were male age, body mass index, smoking, semen values, % sperm DNA fragmentation, fertilization rate and pregnancy outcome. The ICSI procedure was performed in all patients per standard protocol. The semen samples were grouped based on % sperm DNA fragmentation into < 15%, 15-30 and > 30% which corresponded to low, moderate and high sperm DNA fragmentation, respectively.

RESULTS

There was no difference in ICSI outcome in low and moderate sperm DNA fragmentation, however, in high sperm DNA fragmentation no patient achieved pregnancy. In this study, 53.19% Saudi men had low, 32.98% moderate and 13.83% high DFI. Semen volume, sperm morphology and fertilization rate did not show any correlation trend with DNA fragmentation, however, sperm concentration and motility were negatively correlated in all DFI categories. The BMI was positively correlated in moderate DFI category and smoking was positively correlated with low DFI category. The age was positively correlated in moderate and high DFI categories.

CONCLUSIONS

The results of this study indicated that 14% Saudi men had high DNA fragmentation. The BMI was positively correlated in moderate DFI category and smoking was positively correlated with low DFI category. The age was positively correlated in moderate and high DFI categories.

The apoptotic, cytotoxic and genotoxic effect of novel binuclear boron-fluoride complex on endometrial cancer

Endometrial cancer (EC) is one of the most common types of gynecologic cancer of the female genital tract; it considered being the fourth leading death factor among other types of cancer. Therefore, developing new anti-cancer agents are crucial for cancer treatment. Based on the potential of Schiff based complexes for the induction of apoptosis, Schiff base compounds, and their metal complexes displayed excellent anticancer properties. In this current study, antiproliferative activity of [L(BF₂)₂] as a novel binuclear boron-fluoride complex was examined to preliminary research in eight different cell lines, HELA, DU-145, PC3, DLD-1, ECC-1, PNT1-A, HT-29, and MCF-7, it was found to have a potent, suppressive effect on human endometrial adenocarcinoma cell line ECC-1. Based on this data, later investigated its apoptotic, cytotoxic, and genotoxic properties on human endometrial adenocarcinoma cell line ECC-1 in different concentrations. Apoptotic and cytotoxic tests such as single cell gel electrophoresis assay (comet assay), DNA fragmentation laddering, acridine orange test for DNA damage, and ELISA for apoptotic measurement was performed. We also gauged the oxidative status by evaluating total antioxidant status (TAS) and total oxidant status (TOS). Oxidative stress index (OSI) was calculated too. As a result [L(BF₂)₂] has been found to have a marvelous effect on ECC-1 cells, especially in damaging their DNA and cause a series of reactions lead to apoptosis. Taken together, it suggests that the [L(BF₂)₂] complex can induce the apoptotic pathway of endometrial cancer cells and is a possible candidate for future cancer treatment studies.

ICSI significantly improved the pregnancy rate of patients with a high sperm DNA fragmentation index

Objective

Correlations between semen parameters and sperm DNA fragmentation index (DFI) were investigated to identify characteristics of sperm without DNA damage that could be used in selecting sperm for intracytoplasmic sperm injection (ICSI). Pregnancy outcomes were compared to determine whether in vitro fertilization (IVF) or ICSI is a better choice for patients who have sperm with a high-DFI.

Methods

Semen analysis was carried out in 388 patients who visited our IVF center for the first time to investigate correlations between sperm DFI and semen parameters. In addition, 1,102 IVF cycles in 867 patients were carried out in the present study; 921 cycles in the low-DFI group (DFI <30%) and 181 cycles in the high-DFI group (DFI ≥30%). Both the low- and high-DFI groups were subdivided into IVF and ICSI cycle groups.

Results

Sperm DFI showed significant inverse correlations with sperm motility (r=−0.435, p<0.001) and morphology (r=−0.153, p<0.05). Sperm DFI also showed significant correlations with rapid motility (r=−0.436, p<0.001), and the kinetic parameters of average-path velocity (r=−0.403) and linearity (r=−0.412). Although there was no significant difference in the pregnancy rates between IVF (48.6%) and ICSI (44.8%) in the low-DFI group, the pregnancy rate of ICSI cycles (44.8%, p<0.05) was significantly higher than IVF cycles (25.0%) in the high-DFI group. No significant difference was observed in the abortion rates between the low-DFI (52 of 921, 5.6%) and high-DFI groups (7 of 181, 3.8%).

Conclusion

ICSI is a better choice than IVF for improving the pregnancy outcomes of patients who have sperm with a high DFI.

A systematic review and meta-analysis to determine the effect of sperm DNA damage on in vitro fertilization and intracytoplasmic sperm injection outcome

Sperm DNA damage is prevalent among infertile men and is known to influence natural reproduction. However, the impact of sperm DNA damage on assisted reproduction outcomes remains controversial. Here, we conducted a meta-analysis of studies on sperm DNA damage (assessed by SCSA, TUNEL, SCD, or Comet assay) and clinical pregnancy after IVF and/or ICSI treatment from MEDLINE, EMBASE, and PUBMED database searches for this analysis. We identified 41 articles (with a total of 56 studies) including 16 IVF studies, 24 ICSI studies, and 16 mixed (IVF + ICSI) studies. These studies measured DNA damage (by one of four assays: 23 SCSA, 18 TUNEL, 8 SCD, and 7 Comet) and included a total of 8068 treatment cycles (3734 IVF, 2282 ICSI, and 2052 mixed IVF + ICSI). The combined OR of 1.68 (95% CI: 1.49–1.89; P < 0.0001) indicates that sperm DNA damage affects clinical pregnancy following IVF and/or ICSI treatment. In addition, the combined OR estimates of IVF (16 estimates, OR = 1.65; 95% CI: 1.34–2.04; P < 0.0001), ICSI (24 estimates, OR = 1.31; 95% CI: 1.08–1.59; P = 0.0068), and mixed IVF + ICSI studies (16 estimates, OR = 2.37; 95% CI: 1.89–2.97; P < 0.0001) were also statistically significant. There is sufficient evidence in the existing literature suggesting that sperm DNA damage has a negative effect on clinical pregnancy following IVF and/or ICSI treatment.

Efficient isolation of sperm with high DNA integrity and stable chromatin packaging by a combination of density-gradient centrifugation and magnetic-activated cell sorting

OBJECTIVE

This study was carried out to investigate the correlations of the sperm DNA fragmentation index (DFI) with semen parameters and apoptosis, and to investigate the effects of density-gradient centrifugation (DGC) and magnetic-activated cell sorting (MACS) on reducing the proportion of sperm with DNA fragmentation and protamine deficiency.

METHODS

Semen analysis and a sperm DNA fragmentation assay were performed to assess the correlations between semen parameters and the DFI in 458 semen samples. Sperm with progressive motility or non-apoptosis were isolated by DGC or MACS, respectively, in 29 normozoospermic semen samples. The effects of DGC or MACS alone and of DGC and MACS combined on reducing the amount of sperm in the sample with DNA fragmentation and protamine deficiency were investigated.

RESULTS

The sperm DFI showed a significant correlation (r=-0.347, p<0.001) with sperm motility and morphology (r=-0.114, p<0.05) but not with other semen parameters. The DFI (11.5%±2.0%) of semen samples was significantly reduced by DGC (8.1%±4.1%) or MACS alone (7.4%±3.9%) (p<0.05). The DFI was significantly further reduced by a combination of DGC and MACS (4.1%±1.3%, p<0.05). Moreover, the combination of DGC and MACS (1.6%±1.1%, p<0.05) significantly reduced the protamine deficiency rate of semen samples compared to DGC (4.4%±3.2%) or MACS alone (3.4%±2.2%).

CONCLUSION

The combination of DGC and MACS may be an effective method to isolate high-quality sperm with progressive motility, non-apoptosis, high DNA integrity, and low protamine deficiency in clinical use.

Measuring Sperm DNA Fragmentation and Clinical Outcomes of Medically Assisted Reproduction: A Systematic Review and Meta-Analysis

Sperm DNA fragmentation has been associated with reduced fertilization rates, embryo quality, pregnancy rates and increased miscarriage rates. Various methods exist to test sperm DNA fragmentation such as the sperm chromatin structure assay (SCSA), the sperm chromatin dispersion (SCD) test, the terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay and the single cell gel electrophoresis (Comet) assay. We performed a systematic review and meta-analysis to assess the value of measuring sperm DNA fragmentation in predicting chance of ongoing pregnancy with IVF or ICSI. Out of 658 unique studies, 30 had extractable data and were thus included in the meta-analysis. Overall, the sperm DNA fragmentation tests had a reasonable to good sensitivity. A wide variety of other factors may also affect the IVF/ICSI outcome, reflected by limited to very low specificity. The constructed hierarchical summary receiver operating characteristic (HSROC) curve indicated a fair discriminatory capacity of the TUNEL assay (area under the curve (AUC) of 0.71; 95% CI 0.66 to 0.74) and Comet assay (AUC of 0.73; 95% CI 0.19 to 0.97). The SCSA and the SCD test had poor predictive capacity. Importantly, for the TUNEL assay, SCD test and Comet assay, meta-regression showed no differences in predictive value between IVF and ICSI. For the SCSA meta-regression indicated the predictive values for IVF and ICSI were different. The present review suggests that current sperm DNA fragmentation tests have limited capacity to predict the chance of pregnancy in the context of MAR. Furthermore, sperm DNA fragmentation tests have little or no difference in predictive value between IVF and ICSI. At this moment, there is insufficient evidence to recommend the routine use of sperm DNA fragmentation tests in couples undergoing MAR both for the prediction of pregnancy and for the choice of treatment. Given the significant limitations of the evidence and the methodological weakness and design of the included studies, we do urge for further research on the predictive value of sperm DNA fragmentation for the chance of pregnancy after MAR, also in comparison with other predictors of pregnancy after MAR.

Impact of sperm DNA damage and oocyte-repairing capacity on trout development

Zygotic repair of paternal DNA is essential during embryo development. In spite of the interest devoted to sperm DNA damage, its combined effect with defect-repairing oocytes has not been analyzed. Modification of the breeding season is a common practice in aquaculture. This practice reduces developmental success and could affect the both factors: sperm DNA integrity and oocyte repair capacity. To evaluate the maternal role, we analyzed the progeny outcome after fertilizing in-season trout oocytes with untreated and with UV-irradiated sperm. We also analyzed the offspring obtained out of season with untreated sperm. The analysis of the number of lesions in 4 sperm nuclear genes revealed an increase of 1.22–11.18 lesions/10 kb in out-of-season sperm, similar to that obtained after sperm UV irradiation (400 µW/cm25 min). Gene expression showed in out-of-season oocytes the overexpression of repair genes (ogg1, ung, lig3, rad1) and downregulation of tp53, indicating an enhanced repairing activity and reduced capacity to arrest development upon damage. The analysis of the progeny in out-of-season embryos revealed a similar profile tolerant to DNA damage, leading to a much lower apoptotic activity at organogenesis, lower hatching rates and increased rate of malformations. The effects were milder in descendants from in-season-irradiated sperm, showing an enhanced repairing activity at epibolia. Results point out the importance of the repairing machinery provided by the oocyte and show how susceptible it is to environmental changes. Transcripts related to DNA damage signalization and repair could be used as markers of oocyte quality.

Developmental origins of male subfertility: role of infection, inflammation, and environmental factors

Male gamete development begins with the specification of primordial cells in the epiblast of the early embryo and is not complete until spermatozoa mature in the epididymis of adult males. This protracted developmental process involves extensive alteration of the paternal germline epigenome. Initially, epigenetic reprogramming in fetal germ cells results in removal of most DNA methylation, including parent-specific epigenetic information. The germ cells then establish sex-specific epigenetic information through de novo methylation and undergo spermatogenesis. Chromatin in haploid germ cells is repackaged into protamines during spermiogenesis, providing further widespread epigenetic reorganization. Finally, after fertilization, epigenetic reprogramming in the preimplantation embryo is necessary for regaining totipotency. These events provide substantial windows during which epigenetic errors either may be corrected or may occur in the germline. There is now increasing evidence that environmental factors such as exposure to toxicants, the parents' and individual's diet, and even infectious and inflammatory events in the male reproductive tract may influence epigenetic reprogramming. This, together with other damage inflicted on the germline chromatin, may result in negative consequences for fertility and health. Large epidemiological birth cohort studies have yielded insight into possible causative environmental factors. Together with experimental animal studies, a clearer view of environmental impacts on fetal development and their intergenerational and even transgenerational effects on reproductive health has emerged and is reviewed in this article.

Sex-sorting of spermatozoa affects developmental competence of in vitro fertilized oocytes in a bull-dependent manner

The aim of the present study was to clarify if flow-cytometric sex-sorting of bovine sperm affected in vitro blastocyst production in different bulls, either in terms of its ability to fertilize the oocyte or by interfering with post-fertilization embryo development. We performed in vitro fertilization (IVF) using both commercially available frozen-thawed X-sorted and non-sorted sperm of 4 Holstein bulls at 3 concentrations (1 × 10⁶, 2 × 10⁶, and 5 × 10⁶ sperm/ml). When fertilization rates were compared, a variation in fertilization rates among different sperm concentrations was detected in 2 bulls, with similar results for X-sorted and non-sorted sperm. However, we found no evidence that the fertilization rates were affected by the sorting process. To investigate effects on embryo development, we determined the optimum sperm concentration for IVF in each bull, which resulted in similar fertilization rates among bulls. We next performed IVF using both X-sorted and non-sorted sperm of the 4 bulls at their optimum sperm concentration and compared in vitro embryo development. Cleavage rates with X-sorted sperm were similar to their non-sorted counterparts. However, significantly reduced blastocyst development was associated with the use of X-sorted sperm in one bull, whereas in the other three bulls, blastocyst development after IVF with X-sorted and non-sorted sperm was similar. In conclusion, in our system, X-sorting affects in vitro blastocyst production by reducing the developmental competence of fertilized oocytes rather than affecting the fertilization ability of the sperm. However, the occurrence of this phenomenon varies among bulls.

Testicular versus ejaculated spermatozoa in ICSI cycles of normozoospermic men with high sperm DNA fragmentation and previous ART failures

As a part of male assessment, conventional sperm parameters including morphologic features have been dedicated as major factors influencing fertilisation and pregnancy rates in assisted reproductive technology (ART). Genomic integrity of spermatozoa has also been found to influence fertility prognosis, and hence, sperm DNA fragmentation index (DFI) has been adopted by many centres to document this entity. Despite several suggested approaches, there is lack of universal consensus on optimising fertility outcomes in males with high sperm DFI. In this context, the results from cycles using testicular spermatozoa (TESA) obtained by aspiration were compared with those of ejaculated spermatozoa (EJ) in normozoospermic subjects with high sperm DFI and previous ART failures. Clinical (41.9% versus 20%) and ongoing pregnancy rates (38.7% versus 15%) were significantly better and miscarriages were lower in TESA group when compared to EJ group. Sperm DFI should be a part of male partner's evaluation following unsuccessful ART attempts. When high DFI is detected (>30%), ICSI using testicular spermatozoa obtained by TESA seems an effective option particularly for those with repeated ART failures in terms of clinical, ongoing pregnancies and miscarriages even though conventional sperm parameters are within normal range.